by Paul Myerberg, USA TODAY Sports

by Paul Myerberg, USA TODAY Sports

After a disappointing close to the regular season, Oregon quarterback Marcus Mariota will return for another run at the Heisman Trophy, the Rose Bowl and, perhaps, the national championship.

Once the leading contender for the 2013 Heisman Trophy before injuries limited his effectiveness, Mariota has decided to return to Oregon for his junior season, the university announced Tuesday.

As a third-year sophomore - he redshirted in 2011, his first season on campus - Mariota is eligible for the NFL draft. Scouts Inc. rated Mariota the No. 3 overall player available with a 96 grade, and ESPN's Mel Kiper Jr. rated him the No. 5 overall player available.

In deciding to return to Eugene, Mariota bolsters the Ducks' chances of reclaiming the Pac-12 championship after a frustrating second half to 2013. Oregon went 2-2 in November, dropping from No. 2 in the USA TODAY Sports Coaches Poll to the outer fringes of the Bowl Championship Series race.

"It is an honor to be a student at the University of Oregon and to have the opportunity to represent our institution on the football field alongside my teammates," Mariota said in a university news release. "I look forward to earning my degree next year and to the rest of my career at this great University."

Mariota has been hampered by a knee injury since a 42-14 win against UCLA on Oct. 26. In the Ducks' last four games - including losses to Stanford and Arizona - he has completed less than 60% of his attempts twice, tossed his only four interceptions on the year and accounted for only 71 rushing yards on 25 carries.

Mariota threw for 3,412 yards and 30 touchdowns despite the sluggish close to the regular season, setting a school season record with 3,994 yards of total offense -.and standing as the only quarterback on the automatic-qualifying level to throw for at least 30 touchdowns in each of the last two years.

His superb statistical season earned Mariota first-team all-Pac-12 honors for the second year in a row. He is the first Pac-12 quarterback to earn matching honors in back-to-back years since former Stanford quarterback Andrew Luck in 2010 and 2011, and the first Oregon quarterback to do so since Chris Miller in 1985 and 1986.

Oregon also announced that center Hroniss Grasu, a three-year starter, would return for his senior season. Also a first-team all-conference pick, Grasu is expected to earn All-America honors for the second year in a row.

"I'm extremely happy to be returning for my senior year," Grasu said. "To be a student-athlete in this community is an honor and an experience I'll continue to cherish with my teammates."